1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
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15 include "delayed_updating/syntax/path.ma".
16 include "delayed_updating/notation/functions/class_c_1.ma".
17 include "ground/lib/subset.ma".
19 include "delayed_updating/syntax/path_depth.ma".
20 include "delayed_updating/syntax/path_height.ma".
22 (* CLOSED CONDITION FOR PATH ************************************************)
24 axiom pcc: relation2 nat path.
27 "closed condition (path)"
30 (* Basic destructions *******************************************************)
33 (š) Ļµ šāØšā©.
35 axiom pcc_d (p) (d) (n:pnat):
36 p Ļµ šāØd+nā© ā pāš±n Ļµ šāØdā©.
39 p Ļµ šāØdā© ā pāš Ļµ šāØādā©.
42 p Ļµ šāØdā© ā pāš Ļµ šāØdā©.
45 p Ļµ šāØdā© ā pāš¦ Ļµ šāØdā©.
47 axiom pcc_des_gen (p) (d):
48 p Ļµ šāØdā© ā d + āÆp = āpā.